Exercise In Heat Flashcards
Are fixed temperatures a good determinant for heat related injury?
No
There are many factors that impact heat related injuries
What are the 3 factors determining overheating
- Climate
- Activity
- Wind
What makes up climate?
a. Ambient air temperature (shade)
b. Mean radiant temperature
c. Absolute humidity
d. Wind
How does the body warm due to convection?
Air temperature exceeds skin temperature
How does the body warm due to radiation?
Direct sunlight temperature higher than skin
How does sweat cool down the body?
The evaporation of sweat cools body
1g of sweat = 2427J of heat lost
What happens when there is humidity and body cooling?
Humidity: makes it harder for water to evaporate due to the high water content in air density
How does wind impact body temperature?
Increases the rate of sweat evaporation. Impacts sweat transport
How does activity cause overheating?
- Activity: Energy is broken into work and heat
Some activities such as cycling are more efficient in creating work vs others e. running
How does clothing contribute to overheating?
- Dry insulation
2. Evaporative resistance
What part of the brain is responsible for temperature control?
Hypothalamus
Describe the process of Hypothalamic temperature control
- Temperature changes
- Hypothalamic/ visceral temperature changes
- Thermal error signal
- Signals to cortex, sweat glands, vessels and muscle to regulate behaviour
What population is most vulnerable to heat?
- older adults
- co-morbidities
- Medication
- Poverty
- Socially isolated
- Working in heat
What is the result of heat stress to the visceral system?
- Less blood to core
- Increased heart output to deliver sufficient blood
What are the symptoms of heat stroke?
- Irrational behaviur, irritability
- Altered consciousness, coma
- Disorientation
- Headache
- Confusion
- Nausea or vomiting
- Collapse, staggering or sluggish feeling
- Diarrhoea
- Profuse sweating
- Excessive thirst
- Rapid pulse
